The present invention relates to a heliostat that is provided with an actively controlled liquid ballast system.
With rising concerns about the limited supply and environmental impact of fossil fuels, much attention is being given to the development of clean, renewable energy sources. The heliostat array concept is one of the more promising of such sources. A heliostat is comprised of a large mirror and the machinery and instrumentation necessary to actuate the mirror such that it can reflect sunlight onto a stationary target throughout the day. A heliostat array is created by disposing a large number of heliostats around a central receptor such that they concentrate sunlight on the receptor. The heat produced by this concentration of sunlight may be used in any number of ways, for example to drive a steam turbine power unit and generate electricity. Very accurate continuous positioning systems are needed for the mirrors. Unfortunately, the prior known systems are expensive and complicated. For example, most conventional heliostats employ large servo motors geared down through a planetary-type transmission to effect the necessary rotation of their axes of rotation.
It is therefore an object of the present application to provide an economical heliostat that operates in a straightforward yet accurate manner.